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      <title>双Token无感刷新 - 交互式测验</title>
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      </style>
    </head>
    <body>
      <div class="main-wrapper">
          <div class="quiz-container">
            <div class="quiz-header">
              <h1>双Token无感刷新 - 交互式测验</h1>
              <p>检验你对文档内容的理解程度</p>
            </div>
            <div id="quiz-content">
                <div class="quiz-body">
                    <div class="progress-bar">
                        <div id="progress-indicator"></div>
                    </div>
                    <div id="question-container">
                      <p id="question-text"></p>
                      <ul class="options-list" id="options-list"></ul>
                    </div>
                    <div id="result-container"></div>
                    <div id="hint-container" class="hint-container"></div>
                </div>
                <div class="quiz-footer" id="quiz-footer">
                  <button id="prev-btn" class="nav-btn">上一题</button>
                  <button id="hint-btn" class="nav-btn" style="background-color: #ffc107; color: #333; box-shadow: 0 4px 12px rgba(255,193,7,0.3);">提示</button>
                  <button id="next-btn" class="nav-btn">下一题</button>
                </div>
            </div>
          </div>
      </div>

      <script>
        const quizData = [
  {
    "question": "在双Token无感刷新机制中，Access Token 和 Refresh Token 的核心职责分别是什么？",
    "options": [
      "Access Token 用于接口访问，时效短；Refresh Token 用于续期，时效长。",
      "Access Token 用于刷新凭证，Refresh Token 用于接口访问。",
      "两者都用于接口访问，但 Refresh Token 的安全级别更高。",
      "Access Token 用于加密通信，Refresh Token 用于解密通信。"
    ],
    "correctAnswerIndex": 0,
    "explanation": "双Token方案的核心在于职责分离。Access Token（门票）作为访问资源的直接凭证，为了安全其有效期通常很短（如2小时）。当它过期后，客户端使用有效期更长（如7天）的Refresh Token（电子手环）去静默地换取一个新的Access Token，从而避免用户重新登录，实现无感刷新。",
    "source": "文档中「为什么你的登录方案总被骂？」部分",
    "hint": "文档中将这两种Token形象地比喻为“纸质门票”和“电子手环”，思考一下它们各自的作用。"
  },
  {
    "question": "当多个前端请求同时发现Access Token过期并尝试刷新时，可能会引发“连环刷新风暴”。文档中提出的关键解决方案是什么？",
    "options": [
      "为每个Refresh Token绑定设备指纹，防止被盗用。",
      "在网关层对新Token进行本地缓存，减少认证次数。",
      "使用Redis原子锁（如setIfAbsent），确保同一时间只有一个请求能执行刷新操作。",
      "采用令牌桶算法对刷新接口进行限流。"
    ],
    "correctAnswerIndex": 2,
    "explanation": "“连环刷新风暴”的本质是一个并发问题。文档中明确指出，解决方案是使用Redis的原子操作（如`setIfAbsent`）来实现分布式锁。当第一个请求开始刷新时，它会获取一个锁，其他并发的刷新请求会因为无法获取锁而失败或等待，从而避免了对认证服务造成冲击。",
    "source": "文档中「这些坑你躲得过吗？ - 1. 连环刷新风暴」部分",
    "hint": "这个问题考察的是如何解决并发场景下的资源竞争。文档中的伪代码展示了一种加锁操作。"
  },
  {
    "question": "为了防止Refresh Token被黑客窃取后可以被无限次使用，文档强调了哪一种重要的安全绑定机制？",
    "options": [
      "IP地址绑定",
      "用户ID绑定",
      "设备指纹绑定",
      "浏览器版本绑定"
    ],
    "correctAnswerIndex": 2,
    "explanation": "文档在“Token劫持漏洞”一节中明确提出，解决方案是将Refresh Token与设备指纹（如通过请求头中的`X-Device-ID`获取）进行绑定。在生成Refresh Token时将设备信息存入其中，在刷新时进行校验。这样一来，即使Token被盗，攻击者在不同的设备上也无法通过校验，从而无法使用该Token。",
    "source": "文档中「这些坑你躲得过吗？ - 2. Token劫持漏洞」部分",
    "hint": "考虑一下如何确保一个Token只能在它最初被颁发的那个特定设备上使用。"
  },
  {
    "question": "在“完美方案设计”的“六大核心机制”中，“旧Refresh Token用完即焚”指的是哪一项机制？",
    "options": [
      "熔断降级",
      "单次有效",
      "滑动过期",
      "使用次数限制"
    ],
    "correctAnswerIndex": 1,
    "explanation": "“单次有效”机制意味着一个Refresh Token一旦被用来成功刷新获取新的Token对，它自身就会立即失效。这种“用完即焚”的策略极大地增强了安全性，即使一个旧的Refresh Token被截获，它也已经作废，无法被用于重放攻击。",
    "source": "文档中「完美方案设计 - 六大核心机制」部分",
    "hint": "这个机制的名称直接描述了它的特性：一个Token只能被有效使用一次。"
  },
  {
    "question": "当用户在手机端刷新了Token，导致PC端被强制下线，这种“多端登录互踢”问题，文档推荐的解决方案是什么？",
    "options": [
      "为每个设备生成完全独立的Access Token和Refresh Token。",
      "采用Token白名单机制，统一管理一个用户下所有有效设备的登录状态。",
      "强制用户在同一时间只能在一个设备上登录。",
      "通过IP地址来区分不同设备的登录会话。"
    ],
    "correctAnswerIndex": 1,
    "explanation": "文档中将“Token白名单”机制比作“银行账户的登录设备管理”。这意味着后端会维护一个列表，记录了某个用户所有已授权登录的设备及其对应的有效Refresh Token。当一个设备刷新时，系统只会更新或轮换该设备对应的Token，而不会影响到白名单中其他设备的有效Token，从而解决了多端互踢的问题。",
    "source": "文档中「这些坑你躲得过吗？ - 3. 多端登录互踢」部分",
    "hint": "文档将这个解决方案类比为银行系统中的一个常见功能，用于管理你可以在哪些设备上登录。"
  },
  {
    "question": "根据“性能优化”章节的压测数据和优化技巧，以下哪项技术被用来实现并行处理，以提升刷新效率？",
    "options": [
      "连接池优化",
      "令牌桶限流",
      "本地缓存",
      "异步刷新（使用CompletableFuture）"
    ],
    "correctAnswerIndex": 3,
    "explanation": "文档中明确提到了“异步刷新”是五大优化技巧之一，并给出了使用`CompletableFuture`的示例代码。通过异步化，刷新Token的操作可以被放入独立的线程池中执行，不会阻塞当前处理请求的线程（例如网关的IO线程），从而提高了系统的吞吐量和响应速度。",
    "source": "文档中「性能优化」部分",
    "hint": "在Java中，哪种技术常用于将耗时操作放到后台线程执行以避免阻塞主线程？"
  },
  {
    "question": "在“安全攻防演练”的“终极防御方案”中，为了应对JWT签名密钥泄露带来的风险，文档提出了哪种主动防御策略？",
    "options": [
      "使用硬件安全模块（HSM）管理密钥。",
      "采用双向TLS认证。",
      "动态密钥轮转，例如每小时更换一次签名密钥。",
      "通过行为分析引擎检测异常登录。"
    ],
    "correctAnswerIndex": 2,
    "explanation": "动态密钥轮转是一种高级安全策略。它通过定期（例如每小时）更换用于签名JWT的密钥，来缩短单个密钥的生命周期。即使旧的密钥被泄露，它也很快会失效，从而将潜在的风险窗口降到最低。这是一种“打不过就换”的有效策略，大大增加了攻击者破解和利用密钥的难度。",
    "source": "文档中「你的认证方案能抗住这五招吗？ - 终极防御方案」部分",
    "hint": "想象一下，如果你的房间钥匙每小时都会换一把新的，那么小偷偷到旧钥匙还有用吗？"
  }
];
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        let score = 0;
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            const totalQuestions = quizData.length;
            const answeredCount = userAnswers.filter(a => a !== null).length;
            const wrongCount = answeredCount - correctCount;
            const skippedCount = totalQuestions - answeredCount;
            const accuracy = totalQuestions > 0 ? Math.round((correctCount / totalQuestions) * 100) : 0;
            const errorRate = totalQuestions > 0 ? Math.round((wrongCount / totalQuestions) * 100) : 0;

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                '<h2>答题报告</h2>' +
                '<div class="score-summary">' +
                '<div class="score-card">' +
                '<h3>得分</h3>' +
                '<p>' + correctCount + ' / ' + totalQuestions + '</p>' +
                '</div>' +
                '<div class="score-card">' +
                '<h3>正确率</h3>' +
                '<p>' + accuracy + '%</p>' +
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                '<div class="score-card">' +
                '<h3>错误率</h3>' +
                '<p>' + errorRate + '%</p>' +
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                '<div class="score-card score-details">' +
                '<table>' +
                '<tr><td>正确</td><td>' + correctCount + '</td></tr>' +
                '<tr><td>错误</td><td>' + wrongCount + '</td></tr>' +
                '<tr><td>未答</td><td>' + skippedCount + '</td></tr>' +
                '</table>' +
                '</div>' +
                '</div>' +
                '<div class="report-actions">' +
                '<button id="review-btn">回顾测验</button>' +
                '<button class="primary" onclick="location.reload()">再试一次</button>' +
                '</div>' +
                '</div>';

            let reportEl = document.querySelector('.final-score-container');
            if (reportEl) {
                reportEl.remove();
            }
            quizContentEl.insertAdjacentHTML('beforeend', finalScoreHtml);
            document.getElementById('review-btn').addEventListener('click', reviewQuiz);
        }

        function reviewQuiz() {
            const reportEl = document.querySelector('.final-score-container');
            if (reportEl) {
                reportEl.remove();
            }

            document.querySelector('.quiz-body').style.display = 'block';
            document.getElementById('quiz-footer').style.display = 'flex';
            
            currentQuestionIndex = 0;
            loadQuestion();
            updateNavigationButtons(); // Ensure nav buttons are correctly displayed
        }

        // Event Delegation for options
        optionsListEl.addEventListener('click', (event) => {
            if (event.target && event.target.matches('li.option-item')) {
                // Check if the question has already been answered
                if (userAnswers[currentQuestionIndex] === null) {
                    const selectedIndex = parseInt(event.target.dataset.index, 10);
                    selectOption(selectedIndex);
                }
            }
        });

        prevBtn.addEventListener('click', goToPreviousQuestion);
        nextBtn.addEventListener('click', goToNextQuestion);
        hintBtn.addEventListener('click', showHint);
        
        // 初始加载
        loadQuestion();
      </script>
    </body>
    </html>
  